1. Field of the Invention
The present invention relates in general to bone marrow biopsy devices and, more particularly, to a bone marrow biopsy device with a grip enhancement feature.
2. Background Art
Bone marrow biopsy devices have been known in the art for many years. In particular, many bone marrow biopsy devices have included a hollow outer cannula with some form of inner rod slidable within the outer cannula. The outer cannula conventionally consists of a proximal end, a distal end and some form of a handle associated with the proximal end. The inner rod may typically take several different forms, including a sharpened stylet for insertion of the bone marrow biopsy needle into a patient, an inner cannula for sampling bone marrow, and/or an ejector rod for forcing the sample out of the outer cannula. The inner rod also typically includes a second or connection handle which may be secured to the handle portion of the outer cannula.
For instance, Baldridge, U.S. Pat. No. 5,357,974, Tretinyak, U.S. Pat. No. 4,403,617, Tretinyak, U.S. Pat. No. 4,630,616, Lee, U.S. Pat. No. 4,655,266 and Strasser et al., U.S. Pat. No. 4,838,282 all disclose bone marrow biopsy devices having a first handle mounted on the outer cannula and a second handle mounted on the inner rod. The first and second handle portions of these devices are constructed from the same material, typically a light weight plastic. Moreover, these handles are usually designed to securably mate with one another, for instance by a locking member, such as that taught in Mittermeier et al., Ser. No. 09/137,854, incorporated herein by reference.
Additionally, several of these bone marrow biopsy devices have included handle features which enhance the ability of a user to both grip and manipulate the bone marrow biopsy needle. For instance, Strasser, U.S. Pat. No. 4,838,282 discloses finger grooves in the outer cannula handle portion, while Tretinyak, U.S. Pat. No. 4,403,617 discloses ridges on both the first and second handle portions to facilitate a users grasping of the device.
Although these and other bone marrow biopsy devices have worked well, it is still to desired to provide an enhanced gripping surface which enhances the feel for a user of the instrument, while at the same time preventing slipping of a hand or fingers which grasp the handle portion of the instrument. It is likewise desired to provide an enhanced gripping surface which works well in condition where water, perspiration or other fluid may be present.
It is further desired to provide a bone marrow biopsy device with a handle having a cushioned gripping portion. In particular, many bone marrow biopsy devices must inherently be forced by a physician for insertion into a patient's bone, thus mandating a firm, tight grip on the handle of the instrument. It is beneficial to provide a softer, cushioned surface to alleviate some of the stress placed on the physician's hand.
It is also desirable to provide a bone marrow biopsy device with a handle which is easily molded, and which includes inserts which add to the weight of the handle and improve weight distribution throughout the handle. It is likewise desirable to provide an inexpensive, easily positioned insert which contributes to a comfortable handle weight, while also enhancing the grip of the handle.
It is also desired to provide a bone marrow biopsy device with a gripping surface which enhances the secured, locking relationship of the outer cannula handle portion to the inner rod handle portion, to facilitate simultaneous use of the outer cannula in conjunction with the inner rod, for insertion, manipulation, and removal of the bone marrow biopsy device from a patient.
These and other objects of the present invention will become apparent in light of the present specification, claims and drawings.